Since 1995, the Descriptors for Avocado (Persea spp.), published by the International Plant Genetic Resource Institute, has provided the descriptive method of choice for all aspects of avocado trait description. A graphic edition has been recently published (Barrientos-Priego et al., 2010). Both guides, however, are problematic in their categorization of fruit shapes as they are not presented on a linear scale and so cannot be easily quantified for identification by mathematical or machine methods.